Method of treating clay



Patented May 27, 1930 UNEED STATES PATENT OFFICE WINFREID G. BUCKLES, OF FARGO, WYOMING, ASSIGNOR TO PAROO DEVELOPMENT COLEPANY, F PABCO, WYOIWING,

A CORPORATION OF DELAWARE METHOD OF TREATING CLAY No Drawing. Application filed April 27,

This invention relates to a method of treating clay. Latter day methods of making clay products, particularly such as brick and high refractories, involve a pretreating of the clay,

consisting, generally, of dampening and pugging the raw clay, and then storing the same for a considerable length of time, running from a few days to as long as six months. It has been found that such treatment imparts greatly increased plasticity and cohesion to the clay. If the clay is repugged it is found to have gained a great deal in workability, drying qualities and burning qualties. In some of the processes of pretreating the clay, heretofore employed, the clay is mixed with water and pugged, then allowed to stand for about two weeks in a pile with wet cloths over it, then repugged and again stored in a pile for an additional length of time, and finally repugged and need Now, while the increased plasticity, cohesion, workability, etc. are highly desirable, it is manifest that the pugging of the stiff mud, the handling into huge piles, the storage over long periods of time, and the rehandling to repug, slows up the process of manufacture, as Well as involving the expenditure of a great deal of time, labor and money.

By the process of the present invention I am able to secure all necessary and desired improvement in the condition of the materials being handled, by treatment in a very simple and inexpensive way, and through a very short period of time, with the result that I produce a highly improved product at a much less cost than has heretofore been possible. I

In my co-pending application, Serial No. 235,755, filed November 25th, 1927, I have disclosed a high refractory consisting of baukite and cretaceous shales, such as those found in Carbon County, Wyoming.

Baukite is a non-spalling refractory which forms an impenetrable glaze. This mineral, only known to metallurgy for the past five years, was originally mined in the Austrian Tyrol, where it was first mined at the little town of Bauchite.

It is as yet almost unknown among the 1928. Serial No. 273,435.

geologists of America, and many people confuse the name with bauxite.

A recent analysis by the Mellon Institute Was as follows:

Ignition loss 1.26 Silica 95.06 Alumina 1.97 Iron oxide 0.457 Titania" 0.27 Lime Trace. Magnesia 0.32 Alkalies 0.30

Softening point Cone 32-33 Bonding test conducted in the standard reheat (1400 C. for 5 hours).

Other analyses show zircon.

The best known silica refractories fuse at about cone 31, while baukite fuses at from cone 32 to cone 33. When heat is applied. to baukite a glaze immediately forms on the surface, which is thereafter totally impenetrable. It is to this peculiar glazing action that its remarkable qualities are due."

The process of the present invention is partlcularly adapted for the treatment of the materials makmg up a product such as that described 1n the aforesaid application, though 1t 1s not to be understood that the invention is limited to the particular materials'there disclosedl/Vhen using the method in the production of a refractory, consisting principally of baukite and a shale, such, for example, as a Dakato shale, said Dakota shale was ground and stored for twenty-four (24) hours in as much water as would be required for the making of a brick consisting of Dakota shale 33%, and baukite 67%. This resulted in producing a shale dust cream, which flows very readily by gravity. This Dakota shale cream was then mixed and pugged with- In addition, it was found baukite, and the reduction of this binder to the form of a free flowing cream manifestly permits it to most intimately penetrate the stone or-baukite, and facilitates the production of a homogeneous mass.

The plasticity of clay is largely dependent upon its colloidal qualities, and the mixing of the shale with the much larger percentage of water than has heretofore been the practice, brings about a much more pronounced microscopic penetration of the shale by the water than would be the case if the shale were merely dampened. This increased penetration by the water is followed by physical and probably by some chemical changes. This penetration and these changes takes place much more rapidly in a cream made up of a percentage of the whole material being employed and then mixed into the whole. than when the proper amount of water is applied to the whole percentage primarily, and the curing done in soft mud or stiff mud formation.

While I have described the invention as used in conjunction with the manufacture of a refractory made up of a baukite base and a shale binder, I wish to say that I have experimented with other clays and have found the method to produce better results than the stifi mud storage curing methods, with practicallyall clays.

The reduction in the expense of operating under the aforesaid process is very great. If a tank be arranged under a storage bin to receive the ground clay from the storage tank, and this tank empty its cream, by gravity, into the pugging machine, very little expense of operation is involved. When contrasted with methods involving the handling of heavy, damp viscous clay into huge piles, it will be very apparent that the present method presents most marked economies.

While I have found twenty-four 24) hours to be a desirable time for storage of the shale in the water, in the form of a cream, this time may be decreased or increased to any desired extent, because advantageous results, over present methods, may be observed, even if the cream be used immediately. However, the best results are attained by storing for at least 24 hours,'as described.

Having described my invention, what I claim is: V v

1. The herein described method of making a high refractory formed, in the main, of a crystalline material and a clay, which consists of storing said clay in finely divided form in that quantity of water necessary for the reduction to moldable condition of the whole mass for a period of time sufficient to permit microscopic penetration of the clay by the water, sai'd quantity of water being sufficient to produce a flowable cream, and thereafter pugging said cream and the crystalline material together.

2. The herein described method of making a high refractory, formed of a finely divided quartzite and a Dakota shale, which consists of grinding the shale and mixing it in finely divided condition with that amount of water necessary for the treatment of the whole mass in bringing the mass to moldable condition, storing the shale in the water in the form of a flowable cream for approximately 24 hours,

and thereafter pugging the cream and the quartzite together. a

4. The herein described step in the making of high refractories, consisting of a creta ceous shale of Carbon County, Wyoming, and a crystalline material such as quartzite, which consists of mixing the shale in a finely divided form with that quantity of water necessary for the bringing of the whole mass to moldable condition, said water being in such quantity as to constitute with the shale a flowable cream, the shale and water being stored in the form of a cream for approximately 24 hours.

5. The herein described method of making a high refractory formed of a finely divided quartzite and a shale which consists of grinding the shale and storing it in finely divided form in water for a period sufficient to permit microscopic pentrati-on of the ground shale by the water, and to bring the whole to a colloidal state, and a flowable cream, and thereafter pugging said cream and the the quartzite together.

'6. The herein described method of making a refractory, formed of a finely divided baukite and a shale, which consists of grinding the shale and mixing it in finely divided condition with that amount of water necessary for the treatment of the whole mass in bringing the mass to moldable condition, storing the shale and the water inthe form of a flowable cream for approximately 24 hours, and thereafter pugging the cream and the baukite together.

7. The herein-described method of making a refractory adapted to resist high heats, which consists of grinding a shale to finely divided form and storing said ground shale in the full quantity of water that is to be used in producing the complete moldable mass, for a period of time sufficient to permit the water to microscopically penetrate the shale, and to bring the whole to a colloidal state and to the form of a flowable cream and thereafter pugging into said cream a suflicient quantity of baukite to produce a mass stiff enough to be subjected to the steps of molding and burning.

8. The hereindescribed method of producing a refractory for resisting high heats, which consists of reducing a shale binder to finely divided form and storing the same in water for such an appreciable period of time as to bring about microscopic penetration of the shale by the water, and the reduction of the mass to the form of a flowable cream, and to a colloidal state, and thereafter pugging said cream and baukite together to produce a moldable mass, the amount of water in which the shale is stored being in quantity all that it is necessary for the production of the Whole moldable mass, and the shale and baukite being substantially in the proportions of shale 33% and baukite 67%.

In testimony whereof I afiix my signature.

WINFRED G. BUCKLES. 

